<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Document</title>
</head>
<body>
  <div id="app">
    <div v-if="number == 1">
      A
    </div>
    <div v-else-if="number == 2">
      B
    </div>
    <div v-else>
     C
    </div>
  </div>
</body>
<script src="/node_modules/vue/dist/vue.js"></script>
<script type="text/javascript">
var vm = new Vue({
   el: '#app',
   data() {
     return {
       number: 1
     }
   }
})
</script>
</html>